
10
EPSON
S1C63406/408 TECHNICAL MANUAL
CHAPTER 1: OUTLINE
<Outline of Mask Option>
(1) OSC1 oscillation circuit
Crystal or CR oscillation can be selected as the OSC1 oscillation circuit.
Refer to Section 4.3.2, "OSC1 oscillation circuit", for details.
(2) OSC3 oscillation circuit
Crystal, ceramic or CR oscillation can be selected as the OSC3 oscillation circuit.
Select item 3 when using a crystal oscillator or item 2 when using a ceramic oscillator. The frequencies
in parentheses are recommended typical values. Refer to Section 4.3.3, "OSC3 oscillation circuit", for
details.
(3) Internal reset circuit
This mask option selects whether the internal reset circuit is used or not. Select a minimum supply
voltage according to the oscillation frequency when this circuit is used.
Refer to Section 2.2.3, "Internal reset circuit", for details.
(4) External reset by simultaneous LOW input to the I/O port (K00–K03)
This function resets the IC when several keys are pressed simultaneously. The mask option is used to
select whether this function is used or not. Further when the function is used, a combination of the
input terminals (K00–K03), which are connected to the keys to be pressed simultaneously, can be
selected. Refer to Section 2.2.2, "Simultaneous low input to terminals K00–K03", for details.
(5) Time authorize circuit for the simultaneous LOW input reset function
When using the external reset function (shown in 4 above), using the time authorize circuit or not can
be selected by mask option. The reset function works only when the input time of simultaneous LOW
is more than the rule time if the time authorize circuit is being used.
Refer to Section 2.2.2, "Simultaneous low input to terminals K00–K03", for details.
(6) Input port pull-up resistor
The mask option is used to select whether the pull-up resistor is supplemented to the input ports or
not. It is possible to select for each bit of the input ports.
Refer to Section 4.4.2, "Mask option", for details.
(7) Output specification of the output port
Either complementary output or N-channel open drain output can be selected as the output specifica-
tion for the output ports. The selection is done in 1-bit units.
Refer to Section 4.5.2, "Mask option", for details.
(8) Output specification of the I/O ports
For the output specification when the I/O ports are in the output mode, either complementary output
or N-channel open drain output can be selected in 1-bit units.
Refer to Section 4.6.2, "Mask option", for details.